From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Mark H Weaver Newsgroups: gmane.lisp.guile.devel Subject: Re: [PATCH] Handle products with exact 0 differently, etc Date: Tue, 01 Feb 2011 19:30:36 -0500 Message-ID: <87oc6vuvkj.fsf@yeeloong.netris.org> References: <87ipx4vtvg.fsf@yeeloong.netris.org> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: dough.gmane.org 1296607327 5054 80.91.229.12 (2 Feb 2011 00:42:07 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Wed, 2 Feb 2011 00:42:07 +0000 (UTC) Cc: guile-devel@gnu.org To: Andy Wingo Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Wed Feb 02 01:42:01 2011 Return-path: Envelope-to: guile-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1PkQnH-0004sE-Jc for guile-devel@m.gmane.org; Wed, 02 Feb 2011 01:41:59 +0100 Original-Received: from localhost ([127.0.0.1]:46384 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PkQdK-0001rU-KD for guile-devel@m.gmane.org; Tue, 01 Feb 2011 19:31:42 -0500 Original-Received: from [140.186.70.92] (port=54225 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PkQdE-0001rE-4K for guile-devel@gnu.org; Tue, 01 Feb 2011 19:31:37 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PkQdD-0006g0-08 for guile-devel@gnu.org; Tue, 01 Feb 2011 19:31:35 -0500 Original-Received: from world.peace.net ([216.204.32.208]:35173) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PkQdC-0006fi-KN for guile-devel@gnu.org; Tue, 01 Feb 2011 19:31:34 -0500 Original-Received: from ip68-9-118-38.ri.ri.cox.net ([68.9.118.38] helo=freedomincluded) by world.peace.net with esmtpa (Exim 4.69) (envelope-from ) id 1PkQd3-0000qT-R3; Tue, 01 Feb 2011 19:31:26 -0500 Original-Received: from mhw by freedomincluded with local (Exim 4.69) (envelope-from ) id 1PkQcG-00080h-Dd; Tue, 01 Feb 2011 19:30:36 -0500 In-Reply-To: (Andy Wingo's message of "Tue, 01 Feb 2011 21:13:36 +0100") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 216.204.32.208 X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Developers list for Guile, the GNU extensibility library" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.devel:11498 Archived-At: >> Subject: [PATCH] Trigonometric functions return exact numbers in some >> cases > > Why would you want this? I'm a developer of Maxima, a free CAS (computer algebra system). I'm interested in building a free CAS on top of Guile, probably with large chunks of functionality adapted from Maxima. As part of this, I would like it to return exact results whenever feasible. If the argument passed to a trig function is a symbolic expression, that will automatically be handled by GOOPS methods for the various operators. However, there are a few exceptions where trig functions applied to simple numbers will never reach GOOPS. I'd like to do the right thing in those cases. Note that this is also the motivation behind my interest in bigfloats, and in making sure that the numeric code is fully extensible. Best, Mark